It is often desirable to decorate molded plastic parts for aesthetic or practical purposes. Injection molded articles are often decorated using inks, screen printing, pad printing, direct electrostatic flocking and hot stamping. These methods are most often post-molding operations requiring additional processing and cost and time. In addition, the resulting quality of the product is often low, due to the low quality of adhesion or unevenness of the coating.
Recently, In-Mold Decoration (IMD) has been developed to incorporate the application of decoration while the part is being molded to eliminate the extra step of post mold decorating. However, a number of problems have developed with the IMD technology. By way of example, the ink or decoration is typically unable to remain stable during the heat and force of injecting the resins into the mold. During resin injection into the mold, the decoration is often dislocated, leading to an unacceptable finished article. The pressure, heat, and shear force exerted on the decoration during resin injection may also cause the decoration surface to become smeared, crushed, or otherwise disturbed during injection molding.